In the past trailers for commercial use that are hauled by heavy trucks have been built with numerous small I-Shape beams. These beams are hot rolled to very tight section and thickness tolerances. These beams comprise a significant part of the weight of a trailer bed. Typically these trailer beams have a plate welded at the end. After fabrication a finish is applied to the beams since they may be exposed to difficult weathering conditions. The hot rolled beams used today are typically expensive to manufacture because there is not a lot of weight in the each section. Steel mills generally prefer to roll larger sections because they can do so more cost effectively and as such increases output.
Previously, concrete formwork systems have benefited from the beam described in U.S. Pat. No. 3,787,020, issued Jan. 22, 1974 to Avery. The beam described therein is a generally I shaped member that is formed out of aluminum and is sold under the AlumaBeam™ trademark of Aluma Building Systems, Inc. Further concrete formwork structures are described in U.S. Pat. No. 4,156,999 issued June, 1979 to Avery and U.S. Pat. No. 3,899,152, issued Aug. 12, 1975 to Avery. These beams have specific geometry for accommodating various installation attributes; the finite shaped member is accurately formed using aluminum extrusion, providing a very precise shape that is light weight. However, aluminum is very expensive, thus these beams are expensive to produce.
In the past the structural steel I, S and W shapes have been used extensively for fabrication of buildings and various types of framing systems. The shape in itself is very efficient structurally, but when customizing small members with connections and providing protective coating the costs per unit weight become very expensive.
It would be desirable to provide alternate structural steel members that may be used in commercial trailers, concrete formwork systems and various framing systems.
Given the need to conserve energy today it would be advantageous to find a means to reduce the weight of the beams
It would be desirable to have light weight structural members that require less handling for installing connections and for finishing.